LEAP YEAR.

New Zealand Herald, Volume LXV, Issue 19838, 7 January 1928, Page 1 (Supplement)

LEAP YEAR.

BY MATANCA.

CHANGES IN THE CALENDAR.

Why leap year ? The question is a little puzzling if one accepts as gospel the statement' that the earth takes 365 days to complete its journey round the sun. It takes really a little longer than that by a considerable fraction of a day, and therefore some allowance must be made in the calendar every now and then to bring its year into step again with astronomical fact. There are, indeed, several sorts of astronomical year, and the whole subject is not by any means so simple as it would be if our sun were a fixed body and the earth's circuit of it took exactly a certain number of days. Without going into the fractions or decimals that are dear to the mathematician's heart, ordinary folk may get a sufficiently accurate explanation of leap year by remembering that this circuit occupies a little less than days. So every fourth calendar year is given an extra day to keep things approximately right, with occasionally a dropping of this "leap year" to prevent the overdoing that such an adjustment would mean if -it were made, without exception, every fourth year. We get thus the basis for the rule as to what years are leap years: Years whose figures are exactly divisible by four, except centesimal years, whose figures must be exactly divisible by 400 to entitle them to rank as leap years. So 1928 is a leap year, and so will 2000 be—but 1900 had but 365 days. 1 Old Ways With Time.

A plaguy business this ordering of the calendar has proved to be. The rough-and-ready methods once used to reckon time had unsuspected pitfalls. The earliest standard unit—the day—occasioned no difficulty, it was determined by the steady rotation of the earth on its axis. Next came the lunar month, from new moon to new moon, an interval of about 29£ days. Later, the recurrence of the seasons suggested the year. Then the trouble began. At first the year was "twelve lunar months—3s4 days. In course of time, it was noted that things were going astray, for this approximation of the year to the seasons was far too rough. Months and seasons were found not to correspond. To get things right, the Jews and the Greeks put in an extra lunar month from time to time. Working on a scheme * somewhat different, the Romans adopted a similar expedient. Their earliest year had been ten months, first called March and the last December—a fact explaining the seemingly inappropriate numerical naming of the last four of our 12 months. A belief in the luck of odd numbers led' them afterwards to adopt a 12-monthly lunar year of 355 days and consequently to add two new months, January and February. , Pranks of the Pontiffs.

There arose the necessity to accommodate this shorter lunar year to the longer solar year, and the expedient of an intercalated year of different duration was naturally employed. But those rare fellows, the Roman pontiffs, who had sole charge of the calendar as of much else, played some queer pranks with a shrewd eye to business. They made the year longer or shorter as it pleased them or their friends, so that a magistrate or a taxfarmer might have a longer or a shorter term of office. They thus side-stepped the legal limits applying to such offices, and in doing this made no bones of the strange dating of the seasons they brought about. Of course there was a row when Julius Caesar, on becoming dictator, found the spring festivals falling in the nominally summer months, and he set to work, with the aid of art Alexandrian astronomer, to clean up the calendar. / What has become known as " the year of confusion, 4b 8.C., was lengthened by him to 445 days to achieve his reform, and his edict gave each succeeding year 365 days, with the exception of every fourth year, which was to have one more. This institution of the Julian calendar, named after him, thus introduced the leap year, and his apportionine of days to the months gave them alternately 31 and 30, with the exception of February, which was to have 2„ days in ordinary vears and 30 in leap years. lie renamed July the month following June, in honour of himself. But the pontiffs later made a mess ol things, in applying the Julian calendar, y making every third year a leap year. bo bv 8 B.C. three leap years too many had been observed, and Augustus, therefore ordained that there should be no more for 12 years, and in the course of his reform renamed after himself the month following July- took a day from February to add to its 30 days, and made the four months Of the year consist respectively of 30 31 30 and 31 days, instead of <sl, «SU, 3l' 30* Augustus thus gave us our modern arrangement of days in the months, but ha left the problsm created Jy the solar year beinp a little less—by 11 m utes and some seconds —than 365 a days. Old Style and New. Many observers, aware of the flaw in the adjustment, made remedial proposals in ?hfsixteenth century; but it was Pope Grecory XIII. who tackled the question earnestly and annulled ten days by papal bul" Associated frith this • edict was-a provision that three of the leap years in each 400 years should be accounted common years The three chosen were those which close the centuries and are not divisible by four. So came the Gregorian calendar, known also as the new style. It had immediate acceptance in many countries, the annulment of ten days being achieved by calling the 10th of December &the 20th. Scotland adopted the new style in 1600 but in England there was pronounced opposition. When at length, in \ 1751, an English Act was passed for regulating the commencement of the year and for correcting the calendar now >n use," there was much popular resentment. Eleven davs had to be dropped, for England had observed 1700 as a leap year, so adding one more to the daysof erior. "Give us back our eleven days, was the ory with which many statesmen were assailed. As countries under the influence of the Greek Church did not a change of papal institution, and 1800wr.s observed by them as a leap year, th ei - arose the difference of twelve days between old style and new, which has persisted. _ ' All this matters little to us now, save those born on a leap year's February Dickens makes a quaint error in his Uur School"—or was he merely chronicling a schoolfellow's exaggeration ?—in telling ol the boy claiming to have been born on the 29th of February and therefore to have only one birthday in five years. Rossini, the composer, when, he was ifi, celebrated what he called his eighteenth birthday, for he was another born on February 29. He wasn't strictly correct in his jest: it was only his seventeenth. He had forgotten that 1800—he was born in 1792—was not a leap year. Nevertheless, there was fine spirit in his declared purpose to "turn over a new leaf and disregard the frivolities of youth ar.d the indiscretions- of his teens."